11

Virtual Virtual CharactersCharacters

Two TypesTwo Types

UserUser

ComputerComputer22

AvatarAvatar

AgentAgent

AvatarsAvatars What affordances do they What affordances do they

provide?provide?

What should/can they look What should/can they look like?like?

How are they be How are they be controlled?controlled?– What should be controlled?What should be controlled?

How do they transform How do they transform real interaction?real interaction?

33

AgentsAgents

How realistic can their How realistic can their behavior be?behavior be?

What is their effect on What is their effect on performance/behavior of performance/behavior of real human?real human?

Where are they be applied?Where are they be applied?

44

Virtual BodiesVirtual Bodies

Virtual CharactersVirtual Characters

Virtual HumansVirtual Humans

55

CopresenceCopresence How do people respond to Virtual Humans?How do people respond to Virtual Humans?

– PI?PI? Being “with” another personBeing “with” another person

– PSI?PSI? Behaving as though that other person is real in spite of Behaving as though that other person is real in spite of

knowledge otherwiseknowledge otherwise

Uses in psychology, interpersonal skills trainingUses in psychology, interpersonal skills training

PI bounded by immersionPI bounded by immersion– Motion and Voice Capture, Display technologyMotion and Voice Capture, Display technology

PSI exists despite best our attempts to ruin itPSI exists despite best our attempts to ruin it– Confirmed by studies in interpersonal behaviors with Confirmed by studies in interpersonal behaviors with

virtual humans (Bailenson, Slater, Johnsen) virtual humans (Bailenson, Slater, Johnsen)

66

Increasing Copresence (PSI)Increasing Copresence (PSI) Rendering should match Rendering should match

capabilitycapability

RenderingRendering– Display, graphics, voice, haptics, Display, graphics, voice, haptics,

motionmotion CapabilitiesCapabilities

– Perception/IntelligencePerception/Intelligence

Better to have low-quality Better to have low-quality rendering with little capability rendering with little capability and high-quality rendering with and high-quality rendering with more capabilitymore capability– Matches user expectationsMatches user expectations

77

The Uncanny ValleyThe Uncanny Valley

88

The Uncanny ValleyThe Uncanny Valley

99

Where can you get Virtual Where can you get Virtual Humans?Humans?

Evolver (Evolver (www.evolver.net))– $40 a piece + $30 for face animation$40 a piece + $30 for face animation– Export directly to format of your choice (Ogre Export directly to format of your choice (Ogre

available)available)– Requires animationRequires animation

MakehumanMakehuman– Free, but more difficult to useFree, but more difficult to use– No hair, no clothingNo hair, no clothing– Requires some rigging + animationRequires some rigging + animation

Make your ownMake your own– Very time consumingVery time consuming– Modeling + Rigging + AnimatingModeling + Rigging + Animating

Commercial – VizardCommercial – Vizard– PriceyPricey– Integrated Virtual Reality SolutionIntegrated Virtual Reality Solution– http://www.worldviz.comhttp://www.worldviz.com

1010

Motion CaptureMotion Capture

Typically expensive: Typically expensive: $6000 for cheapest $6000 for cheapest commercial setup, commercial setup, usually about $250kusually about $250k

Typically requires Typically requires offline stepoffline step

FAASTFAAST– http://http://

www.youtube.com/www.youtube.com/watch?v=Up-9xdXGIQYwatch?v=Up-9xdXGIQY

Face arguably most Face arguably most important…important…

1111

Facial Motion CaptureFacial Motion Capture More challenging than More challenging than

body motion capturebody motion capture– Soft body trackingSoft body tracking– Must map to control Must map to control

pointspoints

Excellent solutions Excellent solutions available for $$$available for $$$– EncumbranceEncumbrance

Some inexpensive Some inexpensive solutions existsolutions exist– LogitechLogitech– Microsoft Face Avatars Microsoft Face Avatars

(coming soon)(coming soon)

1212

Eye Motion CaptureEye Motion Capture

1313

Similar problem to Similar problem to face motion captureface motion capture

Head Mounted and Head Mounted and Desktop solutionsDesktop solutions

Can be Can be incorporated into incorporated into an HMDan HMD

Noisy in practiceNoisy in practice

Non-Mocap AnimationNon-Mocap Animation

Animation packageAnimation package– Autodesk 3D Studio Max, Maya, Motion BuilderAutodesk 3D Studio Max, Maya, Motion Builder

Free for studentsFree for students

– BlenderBlender Free, open sourceFree, open source

– Motion capture data often a good starting pointMotion capture data often a good starting point MixamoMixamo

– Online site to create and mix together Online site to create and mix together animations that have been previously createdanimations that have been previously created

1414

Synthesized AnimationsSynthesized Animations Computer creates animations based on goalsComputer creates animations based on goals

– Fundamentally an AI problem (how do humans do it?)Fundamentally an AI problem (how do humans do it?)

Gaze controlGaze control– Often used for both avatars and agentsOften used for both avatars and agents

Reaching and graspingReaching and grasping– Smart objectsSmart objects

Some physics simulations exist (difficult to make realistic Some physics simulations exist (difficult to make realistic and real-time)and real-time)– Similar to robotics problemsSimilar to robotics problems

1515

Intelligent Agent BehaviorIntelligent Agent Behavior Crowd SimulationsCrowd Simulations

– Large battle scenesLarge battle scenes– Surveillance TrainingSurveillance Training– Virtual world populationVirtual world population

Local interaction modelsLocal interaction models– GazeGaze

One-on-oneOne-on-one Multi-partyMulti-party

– ConversationConversation www.virtualpeoplefactory.com www.personalityforge.com

Good conference: ACM Intelligent Virtual AgentsGood conference: ACM Intelligent Virtual Agents1616

Wizard-of-OzWizard-of-Oz Fake virtual human Fake virtual human agentagent

User led to believe virtual User led to believe virtual human is computer controlledhuman is computer controlled

Typically used for studies on Typically used for studies on interpersonal behaviors with interpersonal behaviors with virtual humansvirtual humans– Are these useful studies?Are these useful studies?

Control scheme may be direct Control scheme may be direct or indirector indirect– Mocap or Selection interfaceMocap or Selection interface

1717